My state taxes go to fund schools and roads. My federal taxes go to fund bombs, warplanes that can't fly in the rain, a failed drug war, and mass surveillance infrastructure.
It's much more defensible to tax for war expenses than it is for schools. War expenses are necessary for the basic premise of a civilization's government - protection of property and life. Schools, not so much.
What's hard to justify is your claim that the present military spending of our government is in any way a proportional response to actual threats to property and life.
We outspend the next seven countries combined[1]. We could fully fund universal higher education with the money we spend on defense and with the remaining dollars still spend more than three times the amount that the next country does.
My state taxes go to fund schools and roads. My federal taxes go to fund bombs, warplanes that can't fly in the rain, a failed drug war, and mass surveillance infrastructure.
That is reason alone for the SALT.